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bioRxiv · 10.1101/2021.06.18.448975

Myosin VI regulates ciliogenesis by promoting the turnover of the centrosomal/satellite protein OFD1

Magistrati, E.·Maestrini, G.·Lince-Faria, M.·Beznoussenko, G.·Mironov, A.·Maspero, E.·Bettencourt Dias, M.·Polo, S.
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Abstract

The actin motor protein myosin VI is a multivalent protein with diverse functions. Here, we identified and characterised a myosin VI ubiquitous interactor, the oral-facial-digital syndrome 1 (OFD1) protein, whose mutations cause malformations of the face, oral cavity, digits, and polycystic kidney disease. We found that myosin VI regulates the localisation of OFD1 at the centrioles and, as a consequence, the recruitment of the distal appendage protein cep164. Myosin VI depletion in non-tumoural cell lines causes an aberrant localisation of OFD1 along the centriolar walls, which is due to a reduction in the OFD1 mobile fraction. Finally, loss of myosin VI triggers a severe defect in ciliogenesis that could be causally linked to an impairment in the autophagic removal of OFD1 from satellites. Altogether, our results highlight an unprecedent layer of regulation of OFD1 and a pivotal role of myosin VI in coordinating the formation of the distal appendages and primary cilium with important implications for the genetic disorders known as ciliopathies.

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Magistrati, E., Maestrini, G., Lince-Faria, M., Beznoussenko, G., Mironov, A., Maspero, E., Bettencourt Dias, M., Polo, S.. 2021-06-19. Myosin VI regulates ciliogenesis by promoting the turnover of the centrosomal/satellite protein OFD1. https://doi.org/10.1101/2021.06.18.448975

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